ObjectiveTo establish a mouse model of rheumatoid arthritis with interstitial lung disease （RA-ILD） in DBA/1 mice using Porphyromonas gingivalis （Pg） infection combined with collagen-induced arthritis （CIA）， and to comprehensively evaluate pathological characteristics in joints， lungs， and serum. MethodsForty DBA/1 mice were randomly divided into four groups， i.e.， Control， Pg infection （Pg）， CIA， and Pg infection combined with CIA （Pg+CIA）， with 10 mice in each group. Arthritis clinical symptoms were evaluated by recording arthritis incidence and clinical scores. Micro-CT scanning was used to assess knee joint pathology. Histopathological changes and collagen deposition in knee joints and lung tissues were analyzed using hematoxylin-eosin （HE） and Masson staining. Immunohistochemistry was performed to detect protein expression of α-smooth muscle actin （α-SMA）， typeⅠ collagen （ColⅠ）， and fibronectin （FN） in lung tissues. Real-time quantitative polymerase chain reaction（Real-time PCR）was used to measure mRNA expression levels of α-SMA， ColⅠ， FN， tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， and IL-1β in lung tissues. Enzyme-linked immunosorbent assay （ELISA） was used to detect serum levels of Pg， cyclic citrullinated peptide （CCP）， and immunoglobulin G （IgG）. ResultsJoint lesions： The CIA and Pg+CIA groups showed 100% arthritis incidence， with evident joint redness， swelling， and deformity. The number of affected limbs was 27 and 28， and clinical scores were 68 and 70， respectively. No obvious clinical symptoms were observed in the Pg group. Histopathological and imaging analyses showed severe joint lesions in the CIA and Pg+CIA groups， with significantly increased histopathological scores， bone mineral density， bone volume fraction， trabecular thickness， and trabecular number compared to the Control group （P<0.01）. No obvious joint pathology was observed in the Pg group. Lung lesions： The Pg+CIA group exhibited marked alveolar inflammation， interstitial inflammatory cell infiltration， and alveolar wall thickening， with pronounced blue staining of collagen fibers. Histopathological scores and collagen area ratios were significantly higher than those of the Control， Pg， and CIA groups （P<0.05）. Lung protein and mRNA expression levels of α-SMA， ColⅠ， and FN were markedly increased， and mRNA levels of IL-6， TNF-α， and IL-1β were significantly elevated compared to the Control group （P<0.05）. Serology： The Pg+CIA group showed significantly higher levels of CCP， Pg， and IgG compared with the Control， Pg， and CIA groups （P<0.05）. ConclusionDBA/1 mice subjected to Pg infection combined with CIA exhibited pronounced symptoms and pathological features of RA-ILD， along with elevated serum anti-CCP antibody levels. This model represents a novel RA-ILD mouse model， providing a valuable experimental tool for investigating RA-ILD pathogenesis and developing new therapeutics， and serves as a basis for establishing anti-cyclic citrullinated peptide antibody （ACPA）-positive RA-ILD animal models.

ObjectivesTo investigate the molecular epidemiological characteristics of HIV-1 infection among men who had sex with men (MSM) in Taizhou City, Zhejiang Province, and to provide a scientific reference for acquired immune deficiency syndrome prevention and control efforts. MethodsThe research subjects were all newly reported MSM population in Taizhou City from 2020 to 2023. Blood samples without antiviral therapy were collected. The HIV-1 pol gene was amplified and sequenced, and the sequences were submitted to the Stanford University drug resistance database to identify the mutation sites and drug resistance. MEGA 11.0 software was used to analyze the nucleic acid sequences, construct phylogenetic tree, and calculate genetic distance of gene sequences. The molecular transmission network diagram of HIV-1 was constructed using Cytoscape_v3.10.1, and the influencing factors of network entry were analyzed by logistic regression. ResultsA total of 363 newly reported HIV-infected MSM patients were included, with a median age [M (P₂₅, P₇₅)] of 34 (26,47) years old. The majority had an educational level of junior high school or below (55.65%). A total of eight subtypes were found, mainly CRF07_BC and CRF01_AE. The primary drug resistance rate was 10.47% (38/363). The optimal molecular network gene distance was 0.019, with a network access rate of 42.70% (155/363), and a total of 47 molecular clusters were formed. Multivariate logistic analyses showed that compared with the CRF01_AE subtype, the clustering risk of CRF07_BC subtype was higher (OR=1.916, 95%CI: 1.191‒3.109), cases with drug resistance had a higher risk of cluster formation than those without drug resistance (OR=2.011, 95%CI: 1.006‒4.080), and recent infected patients had a lower risk of entering the largest molecular cluster than long-term infected patients (OR=0.376, 95%CI: 0.137‒0.928). ConclusionThe newly diagnosed infections among the MSM population are active in Taizhou City, Zhejiang Province, with a high level of primary drug resistance. Individuals carrying drug-resistant strains are more likely to cluster. Drug resistance monitoring should be strengthened to prevent further spread of drug-resistant strains in the network.

BACKGROUND: Bile acids (BAs) facilitate the progression of gastric intestinal metaplasia (GIM). Long non-coding RNAs (lncRNAs) dysregulation was observed along with the initiation of gastric cancer. However, how lncRNAs function in GIM remains unclear. This study aimed to explore the role and mechanism of lncRNA PVT1 in GIM, and provide a potential therapeutic target for GIM treatment. METHODS: We employed RNA sequencing (RNA-seq) to screen dysregulated lncRNAs in gastric epithelial cells after BA treatment. Bioinformatics analysis was conducted to reveal the regulatory mechanism. PVT1 expression was detected in 21 paired biopsies obtained under endoscopy. Overexpressed and knockdown cell models were established to explore gene functions in GIM. Molecular interactions were validated by dual-luciferase reporter assay, RNA immunoprecipitation (RIP), and chromatin immunoprecipitation (Ch-IP). The levels of relative molecular expression were detected in GIM tissues. RESULTS: We confirmed that lncRNA PVT1 was upregulated in BA-induced GIM model. PVT1 promoted the expression of intestinal markers such as CDX2 , KLF4 , and HNF4α . Bioinformatics analysis revealed that miR-34b-5p was a putative target of PVT1 . miR-34b-5p mimics increased CDX2 , KLF4 , and HNF4α levels. Restoration of miR-34b-5p decreased the pro-metaplastic effect of PVT1 . The interactions between PVT1 , miR-34b-5p, and the downstream target HNF4α were validated. Moreover, HNF4α could transcriptionally activated PVT1 , sustaining the GIM phenotype. Finally, the activation of the PVT1 /miR-34b-5p/ HNF4α loop was detected in GIM tissues. CONCLUSIONS BAs facilitate GIM partially via a PVT1/miR-34b-5p/HNF4α positive feedback loop. PVT1 may become a novel target for blocking the continuous development of GIM and preventing the initiation of gastric cancer in patients with bile reflux.
Humans ; RNA, Long Noncoding/metabolism* ; MicroRNAs/metabolism* ; Hepatocyte Nuclear Factor 4/genetics* ; Bile Acids and Salts ; Kruppel-Like Factor 4 ; Metaplasia/metabolism*

The renin-angiotensin-aldosterone system (RAAS) is crucial for regulating blood pressure and maintaining fluid balance, while clock genes are essential for sustaining biological rhythms and regulating metabolism. There exists a complex interplay between RAAS and clock genes that may significantly contribute to the development of various cardiovascular and metabolic diseases. Although current literature has identified correlations between these two systems, the specific mechanisms of their interaction remain unclear. Moreover, the interaction patterns under different physiological and pathological conditions need further investigation. This review summarizes the synergistic roles of the RAAS and clock genes in cardiovascular diseases, explores their molecular mechanisms and pathophysiological connections, discusses the application of chronotherapy, and highlights potential future research directions, aiming to provide novel insights for the prevention and treatment of related diseases.
Humans ; Renin-Angiotensin System/genetics* ; Cardiovascular Diseases/genetics* ; CLOCK Proteins/physiology* ; Animals

In order to investigate whether the effect of Yuxuebi Tablets on the peripheral and central inflammation resolution of mice with inflammatory pain is related to their regulation of G protein-coupled receptor 37(GPR37), an inflammatory pain model was established by injecting complete Freund's adjuvant(CFA) into the paws of mice, with a sham-operated group receiving a similar volume of normal saline. The mice were assigned randomly to the sham-operated group, model group, ibuprofen group(91 mg·kg~(-1)), and low-, medium-, and high-dose groups of Yuxuebi Tablets(60, 120, and 240 mg·kg~(-1)). The drug was administered orally from days 1 to 19 after modeling. Von Frey method and the hot plate test were used to detect mechanical pain thresholds and heat hyperalgesia. The levels of interleukin-10(IL-10) and transforming growth factor-beta(TGF-β) in the spinal cord were quantified using enzyme-linked immunosorbent assay(ELISA), and the mRNA and protein expression of GPR37 in the spinal cord was measured by real-time quantitative reverse transcription PCR(qRT-PCR) and Western blot. Additionally, immunofluorescence was used to detect the expression of macrosialin antigen(CD68), mannose receptor(MRC1 or CD206), and GPR37 in dorsal root ganglia, as well as the expression of calcium-binding adapter molecule 1(IBA1), CD206, and GPR37 in the dorsal horn of the spinal cord. The results showed that compared with those of the sham-operated group, the mechanical pain thresholds and hot withdrawal latency of the model group significantly declined, and the expression of CD68 in the dorsal root ganglia and the expression of IBA1 in the dorsal horn of the spinal cord significantly increased. The expression of CD206 and GPR37 significantly decreased in the dorsal root ganglion and dorsal horn of the spinal cord, and IL-10 and TGF-β levels in the spinal cord were significantly decreased. Compared with those of the model group, the mechanical pain thresholds and hot withdrawal latency of the high-dose group of Yuxuebi Tablets significantly increased, and the expression of CD68 in the dorsal root ganglion and IBA1 in the dorsal horn of the spinal cord significantly decreased. The expression of CD206 and GPR37 in the dorsal root ganglion and dorsal horn of the spinal cord significantly increased, as well as IL-10 and TGF-β levels in the spinal cord. These findings indicated that Yuxuebi Tablets may reduce macrophage(microglial) infiltration and foster M2 macrophage polarization by enhancing GPR37 expression in the dorsal root ganglia and dorsal horn of the spinal cord of CFA-induced mice, so as to improve IL-10 and TGF-β levels, promote resolution of both peripheral and central inflammation, and play analgesic effects.
Inflammation/genetics* ; Pain/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Animals ; Mice ; Freund's Adjuvant/pharmacology* ; Ibuprofen ; Pain Threshold/drug effects* ; Hyperalgesia/genetics* ; Ganglia, Spinal ; Interleukin-10/genetics* ; Transforming Growth Factor beta/genetics* ; Reverse Transcriptase Polymerase Chain Reaction ; Tablets ; Receptors, G-Protein-Coupled

This study aimed to explore the therapeutic mechanisms of Colquhounia Root Tablets(CRT) in treating diabetic kidney disease(DKD) by integrating biomolecular network mining with animal model verification. By analyzing clinical transcriptomics data, an interaction network was constructed between candidate targets of CRT and DKD-related genes. Based on the topological eigenvalues of network nodes, 101 core network targets of CRT against DKD were identified. These targets were found to be closely related to multiple pathways associated with type 2 diabetes, immune response, and metabolic reprogramming. Given that immune-inflammatory imbalance driven by metabolic reprogramming is one of the key pathogenic mechanisms of DKD, and that many core network targets of CRT are involved in this pathological process, receptor for advanced glycation end products(RAGE)-reactive oxygen species(ROS)-phosphatidylinositol 3-kinase(PI3K)-protein kinase B(AKT)-nuclear factor-κB(NF-κB)-NOD-like receptor family pyrin domain containing 3(NLRP3) signaling axis was selected as a candidate target for in-depth research. Further, a rat model of DKD induced by a high-sugar, high-fat diet and streptozotocin was established to evaluate the pharmacological effects of CRT and verify the expression of related targets. The experimental results showed that CRT could effectively correct metabolic disturbances in DKD, restore immune-inflammatory balance, and improve renal function and its pathological changes by inhibiting the activation of the RAGE-ROS-PI3K-AKT-NF-κB-NLRP3 signaling axis. In conclusion, this study reveals that CRT alleviates the progression of DKD through dual regulation of metabolic reprogramming and immune-inflammatory responses, providing strong experimental evidence for its clinical application in DKD.
Animals ; Diabetic Nephropathies/metabolism* ; Receptor for Advanced Glycation End Products/genetics* ; NF-kappa B/genetics* ; Signal Transduction/drug effects* ; Rats ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics* ; Proto-Oncogene Proteins c-akt/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Phosphatidylinositol 3-Kinases/genetics* ; Reactive Oxygen Species/metabolism* ; Humans ; Plant Roots/chemistry* ; Rats, Sprague-Dawley ; Tablets/administration & dosage*

A combination of the "disease-syndrome-symptom" approach was used to study the syndrome characterization and features of dampness-heat obstruction syndrome in papain-induced knee osteoarthritis(KOA) model rats during the disease process. Forty-eight male SD rats were randomly divided into sham and model groups. The KOA model was established by injecting a mixture of papain and L-cysteine into the joint cavity on days 1, 3, and 5. During the 8 weeks following model establishment, the rats were assessed weekly for the plantar mechanical pain threshold, knee joint diameter, local skin temperature of the knee joint, weight-bearing difference between the two hind feet, and the modified Lequesne MG score of the knee joint. Samples were collected at 1, 2, 4, 6, and 8 weeks after model establishment to observe the gross lesions in cartilage and synovium. Histopathological changes in joint tissues were examined using hematoxylin-eosin, Masson's trichrome, and Senna red O-solid green staining. ELISA and immunohistochemical analysis were performed to detect the levels of interleukin(IL)-1β, IL-6, tumor necrosis factor(TNF)-α, prostaglandin E2(PGE2), and the expression of aquaporins(AQP) 1 and 3 in serum and synovium. The results showed that the ink score of articular cartilage in the model group significantly increased from 4 to 8 weeks, the cartilage Mankin's score and the percentage of Masson-positive area in cartilage increased significantly from 1 to 8 weeks. The percentage of red-stained area for cartilage proteoglycans decreased significantly from 1 to 8 weeks. The synovitis score from 1 to 6 weeks and the percentage of blue-stained collagen fibers in the synovium from 1 to 8 weeks increased significantly, with statistically significant differences compared to the sham group. The mechanical pain threshold in the model group significantly decreased from 1 to 8 weeks, the knee joint diameter significantly increased from 1 to 6 weeks, and the local skin temperature of the knee joint, the weight-bearing difference between the two hind feet, and the modified Lequesne MG score from 1 to 5 weeks significantly increased, all with statistically significant differences compared to the sham group. The levels of IL-1β, IL-6, TNF-α, and PGE2 in serum and synovium of the model group significantly increased from 1 to 6 weeks. Serum TNF-α and PGE2, and synovial IL-1β, also significantly increased at 8 weeks. The levels of cartilage AQP1 and AQP3 significantly increased from 1 to 4 weeks, while synovial AQP1 and AQP3 increased significantly from 1 to 6 weeks, with all differences statistically significant compared to the sham group. In conclusion, papain-induced KOA rats exhibited pathological changes, including articular cartilage degeneration and synovial inflammation, within 1 week of induction. The KOA rats showed characteristics of dampness-heat obstruction syndrome, such as joint pain, swelling, elevated skin temperature, and decreased function, as well as increased inflammatory factors and AQP1、AQP3 in serum and joint tissues within 5 to 6 weeks of disease onset. These results provide an experimental model for studying the syndromes of KOA with dampness-heat obstruction syndrome.
Animals ; Male ; Rats, Sprague-Dawley ; Rats ; Osteoarthritis, Knee/physiopathology* ; Disease Models, Animal ; Humans ; Interleukin-1beta/metabolism* ; Interleukin-6/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Knee Joint/pathology*

Panax species are mostly valuable medicinal plants. While some species' seeds are sensitive to dehydration, the dehydration tolerance of seeds from other Panax species remains unclear. The phospholipase D(PLD) gene plays an important role in plant responses to dehydration stress. However, the characteristics of the PLD gene family and their mechanisms of response to dehydration stress in seeds of Panax species with different dehydration tolerances are not well understood. This study used seeds from eight Panax species to measure the germination rates and PLD activity after dehydration and to analyze the correlation between dehydration tolerance and seed traits. Bioinformatics analysis was also conducted to characterize the PnPLD and PvPLD gene families and to evaluate their expression patterns under dehydration stress. The dehydration tolerance of Panax seeds was ranked from high to low as follows: P. ginseng, P. zingiberensis, P. quinquefolius, P. vietnamensis var. fuscidiscus, P. japonicus var. angustifolius, P. japonicus, P. notoginseng, and P. stipuleanatus. A significant negative correlation was found between dehydration tolerance and seed shape(three-dimensional variance), with flatter seeds exhibiting stronger dehydration tolerance(r=-0.792). Eighteen and nineteen PLD members were identified in P. notoginseng and P. vietnamensis var. fuscidiscus, respectively. These members were classified into five isoforms: α, β, γ, δ, and ζ. The gene structures, subcellular localization, physicochemical properties, and other characteristics of PnPLD and PvPLD were similar. Both promoters contained regulatory elements associated with plant growth and development, hormone responses, and both abiotic and biotic stress. During dehydration, the PLD enzyme activity in P. notoginseng seeds gradually increased as the water content decreased, whereas in P. vietnamensis var. fuscidiscus, PLD activity first decreased and then increased. The expression of PLDα and PLDδ in P. notoginseng seeds initially increased and then decreased, whereas in P. vietnamensis var. fuscidiscus, the expression of PLDα and PLDδ consistently decreased. In conclusion, the dehydration tolerance of Panax seeds showed a significant negative correlation with seed shape. The dehydration tolerance in P. vietnamensis var. fuscidiscus and dehydration sensitivity of P. notoginseng seeds may be related to differences in PLD enzyme activity and the expression of PLDα and PLDδ genes. This study provided the first systematic comparison of dehydration tolerance in Panax seeds and analyzed the causes of tolerance differences and the optimal water content for long-term storage at ultra-low temperatures, thus providing a theoretical basis for the short-term and ultra-low temperature long-term storage of medicinal plant seeds with varying dehydration tolerances.
Seeds/metabolism* ; Panax/physiology* ; Plant Proteins/metabolism* ; Gene Expression Regulation, Plant ; Phospholipase D/metabolism* ; Plants, Medicinal/enzymology* ; Germination ; Multigene Family ; Water/metabolism* ; Dehydration ; Phylogeny

This study adopted a three-dimensional "effect-dose-mechanism" evaluation system to screen the optimal regimen of Yuxuebi Tablets(YXB) combined with ibuprofen(IBU) for chronic musculoskeletal pain(CMP) intervention and elucidate its pharmacological mechanism, so as to provide a scientific basis for the clinical application of the regimen. The experiments were conducted using 8-week-old ICR mice, which were randomly divided into sham operation(sham) group, model(CFA) group, IBU group, YXB group, stasis paralysis tablets combined with ibuprofen low-dose group(IBU-L-YXB), stasis paralysis combined with ibuprofen high-dose group(IBU-H-YXB), stasis paralysis tablets combined with ibuprofen high-dose with ibuprofen discontinuation on the 10th day of administration(IBU-10-YXB), and stasis paralysis tablets combined with ibuprofen high-dose with ibuprofen halving on the 10th day of administration(IBU-1/2-YXB) group. An animal model was established using the CFA plantar injection method. On D0(the second day post-modeling), the success of model establishment was assessed, followed by continuous drug administration for 18 consecutive days from D1 to D18. During this period, mechanical pain threshold was measured by the Von Frey test; thermal hyperalgesia was detected by the hot plate test, and depression-like behavior was observed by the tail suspension test. After treatment, peripheral blood was collected from all groups for complete blood biochemical analysis, and the injected feet of the sham, CFA, IBU, YXB, IBU-YXB, and IBU-10-YXB groups were subjected to oxylipin metabolomics analysis. Immunofluorescence double staining was further performed to detect the co-expression of key oxylipin metabolic enzymes(COX2, LTA4H, and 5/12/15-LOX) and macrophage marker CD68 in the sham, CFA, IBU, and YXB-L/M/H groups. Subsequently, confirmatory analysis of positive indicators was conducted in the sham, CFA, IBU, YXB, IBU-YXB, and IBU-10-YXB groups. On D6(acute phase), mechanical pain sensitivity data showed that compared with the CFA group, only the three combination groups(IBU-YXB, IBU-10-YXB, and IBU-1/2-YXB) exhibited significantly increased paw withdrawal thresholds. On D17(chronic phase), only the IBU-10-YXB group showed a mechanical pain threshold significantly higher than all other monotherapy and combination groups. On D17, thermal pain data showed that compared with the CFA group, all groups except IBU-1/2-YXB had significantly prolonged paw withdrawal latency. On D18, tail suspension data showed that compared with the CFA group, the YXB, IBU-YXB, and IBU-10-YXB groups had significantly reduced immobility time. In summary, IBU-10-YXB stably improved the core symptoms of acute and chronic inflammatory pain. Complete blood count data showed that compared with the sham group, the CFA group had significantly increased mean platelet volume(MPV), while compared with the CFA group, the IBU-YXB and IBU-10-YXB groups had significantly reduced MPV. Moreover, the platelet distribution width(PDW) of the IBU-10-YXB group was further reduced compared with the CFA group. These data suggest that the IBU-10-YXB combination regimen has superior effects on inflammation and blood circulation improvement compared with other treatment groups. At the mechanistic level, each treatment group differentially regulated pro-inflammatory and pro-resolving oxylipin(SPM). Specifically, compared with the CFA group, the IBU and IBU-YXB groups significantly inhibited the synthesis of the prostaglandin family downstream of COX2, reducing pro-inflammatory oxylipins PGD2 and 6-keto-PGF1α but inhibiting PGE1 and PGE2, which played positive roles in peripheral circulation, vasodilation, and inflammation resolution. Compared with the CFA group, the YXB group tended to inhibit the pro-inflammatory oxylipin LTB4 downstream of LTA4H and increase SPMs such as LXA4. The IBU-10-YXB group bidirectionally regulated pro-inflammatory oxylipins and SPMs. Compared with IBU, IBU-10-YXB significantly inhibited the pro-inflammatory mediator 5-HETE. Meanwhile, IBU-10-YXB broadly upregulated SPMs, as evidenced by significant upregulation of LXA4 compared with the CFA group, significant upregulation of LXA5 compared with the IBU and IBU-YXB groups, significant upregulation of RvD1 compared with the CFA group and all other treatment groups, and significant upregulation of RvD5 compared with the sham group. Immunofluorescence double staining results were as follows: compared with the CFA group, the IBU group specifically inhibited the oxylipin metabolic enzyme COX2. In the YXB group, COX2, LTA4H, and 5/12-LOX were significantly inhibited. Within the optimal analgesic dose range, YXB's inhibitory effects on COX2 and LTA4H were dose-dependent, while its inhibitory effects on 5/12-LOX were inversely dose-dependent. The two combination groups(IBU-YXB and IBU-10-YXB) inhibited COX2 and LTA4H without significantly affecting 5-LOX, while IBU-10-YXB further significantly inhibited 12-LOX. These results suggest that the IBU-10-YXB combination regimen effectively maintains stable inhibition of COX2, LTA4H, and 12-LOX while enhancing 5-LOX expression. This combinatorial strategy effectively suppresses pro-inflammatory oxylipins and promotes SPM biosynthesis, overcoming IBU's analgesic ceiling effect and its blockade of pain resolution pathways while compensating for YXB's inability to effectively intervene in acute pain and inflammation. Therefore, it achieves more stable anti-inflammatory, analgesic, and antidepressant effects.
Animals ; Ibuprofen/administration & dosage* ; Mice ; Mice, Inbred ICR ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Musculoskeletal Pain/immunology* ; Tablets ; Humans ; Chronic Pain/metabolism* ; Drug Therapy, Combination ; Disease Models, Animal

OBJECTIVES: To investigate the effects of hyperoxia on the expression of N-methyl-D-aspartate receptor 1 (NMDAR1) and its synapse-associated molecules, including cannabinoid receptor 1 (CB1R), postsynaptic density 95 (PSD95), and synapsin (SYN), in the hippocampus of neonatal rats. METHODS: One-day-old Sprague-Dawley neonatal rats were randomly divided into a hyperoxia group and a control group (n=8 per group). The hyperoxia group was exposed to 80% ± 5% oxygen continuously, while the control group was exposed to room air, for 7 days. At 1, 3, and 7 days after hyperoxia exposure, hematoxylin and eosin (HE) staining was used to observe histopathological changes in the brain. The expression levels of NMDAR1, CB1R, PSD95, and SYN proteins and mRNAs in the hippocampus were detected by immunohistochemistry, Western blotting, and quantitative real-time PCR. RESULTS: After 7 days of hyperoxia exposure, the hyperoxia group showed decreased neuronal density and disordered arrangement in brain tissue. Compared with the control group, after 1 day of hyperoxia exposure, CB1R mRNA and both NMDAR1 and CB1R protein expression in the hyperoxia group were significantly downregulated, while SYN protein expression was significantly upregulated (P<0.05). After 3 days, mRNA expression of NMDAR1, CB1R, and SYN was significantly decreased (P<0.05); NMDAR1 and CB1R protein expression was significantly downregulated (P<0.05), while PSD95 and SYN protein expression was significantly upregulated (P<0.05). After 7 days of hyperoxia, the protein expression of NMDAR1 and CB1R was significantly upregulated (P<0.05). CONCLUSIONS Continuous hyperoxia exposure induces time-dependent changes in the expression levels of NMDAR1 and its synapse-associated molecules in the hippocampus of neonatal rats.
Animals ; Receptors, N-Methyl-D-Aspartate/genetics* ; Rats, Sprague-Dawley ; Hippocampus/pathology* ; Rats ; Animals, Newborn ; Receptor, Cannabinoid, CB1/genetics* ; Hyperoxia/metabolism* ; Disks Large Homolog 4 Protein/genetics* ; Synapsins/genetics* ; Synapses ; Male ; Female ; RNA, Messenger/analysis*